Teak mast collar idea...

[groundhog]

k,
Heres my idea.
I got a bunch of teak boards..
Im gonna glue them together and make a teak block.
(simplified explanation so you can imagine better)
Then Im gonna make it into an oval doughnut shape.
Then im gonna cut it in half
Then I got two bronze hinges on order
Then im gonna put the teak block around the mast and put the hinges on and hammer in the hinge pins.
Then im gonna screw in bunches of spring blocks.

Sound good?
Will i crease my mast and make it all fall down?
groundhog

[arf145]

How is the collar being held down?

[Faster]

Deck stepped or keel stepped?

[mitiempo]

What are you trying to accomplish?

[Faster]

I think he's trying to create a base for turning blocks at the mast to run rigging aft....

[mitiempo]

It won't make your mast fall down but when force is applied the teak collar will move up the mast. Better to use a metal base under the mast that is designed for these loads.

[groundhog]

Oh....

The mast is deck stepped.
On the traverse back to the cockpit, the lines have to travel uphill over about a 10 inch rise in the cabin roof. So my idea for the collar is that the spring blocks, when standing will be at the perfect height for the lines to travel right at the cabin roof level.

I may have a set screw or two to stop upward travel.

My main concern here is the top and bottom collar edge forces trying to crimp the mast as the blocks are loaded with the lines.

I have seen pictures of metal mast collars. These are usually thin (height wise) affairs, but are anchored with multiple screws. The loading is on the screws.

Here the loading will be of the teak against the mast surface.
I think if I make it thick enough (height wise) the creasing forces on the top and bottom teak edges deminish?

Would 3 inches be too thin?

groundhog

[groundhog]

.... also, it just occured to me, when loaded, the resultant force of the blocks will not be in a direction straight up the mast (worse) but in a 45 degree angle toward the cockpit and upwards...(better)

this will relieve some of the crimping forces. and turn them into more of a pulling on the base of the mast toward the cockpit.

[mitiempo]

Bolts, not multiple screws.

What kind of boat? When tightening the halyard a lot of force is taken by the mast collar - it has been known to lift decks if attached in that manner. Any set screws will dig into the teak and not be very effective.

[mitiempo]

It will find the weakest part, which will be the teak or whatever is holding it in place.